Late last year I had an excellent opportunity to spend a few days in Camaret-sur-Mer, which is in the Finistère department in north western France. My client was interested in purchasing a 1988 Beneteau 535E sailing yacht and had asked me to go out there to survey it. I'm not going to go into the details of the survey here, but if you are interested, there's a link to the survey report on the sample reports page of my website.
Just the other day on a boating chat forum I saw a discussion thread that reminded me about a particular defect that I had found on the boat. The topic was asking about the best way to adjust the backstay tension on a masthead rigged boat. The Beneteau that I inspected in France was a Bermudian sloop with a masthead rig. The single backstay featured a hydraulically operated tensioner, adjusted by a winch handle. It appeared that the backstay tension had been set up at some point as there was a mark on the tensioner to indicate an optimum or maximum tension that should be applied.
I don't have conclusive proof, and I never suggested this in my report (keeping to the facts!), but I suspect that the cracks in the cockpit were related to the rig being over-tensioned at some point. If not, then the boat had certainly seen some heavy sailing. The photos below show the cracks.
Just the other day on a boating chat forum I saw a discussion thread that reminded me about a particular defect that I had found on the boat. The topic was asking about the best way to adjust the backstay tension on a masthead rigged boat. The Beneteau that I inspected in France was a Bermudian sloop with a masthead rig. The single backstay featured a hydraulically operated tensioner, adjusted by a winch handle. It appeared that the backstay tension had been set up at some point as there was a mark on the tensioner to indicate an optimum or maximum tension that should be applied.
I don't have conclusive proof, and I never suggested this in my report (keeping to the facts!), but I suspect that the cracks in the cockpit were related to the rig being over-tensioned at some point. If not, then the boat had certainly seen some heavy sailing. The photos below show the cracks.
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| Starboard cockpit coaming |
They were located on both sides of the cockpit. The photos don't illustrate this, but the texture of the cracking was very rough and one could see that the gelcoat between the cracks had 'bunched up'.
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| Close-up of gel-coat cracks |
As a Surveyor and Professional Engineer, I don't find it hard to visualise that as the backstay is tensioned, the deck goes into compression and the longitudinally stiff coaming is forced forwards and into the relatively flexible panel that is the saloon aft bulkhead. The concentration of stress at this corner is higher than adjacent material, leading to localised deformation and damage. Without being able to access the internal surface of the bulkhead and coaming, I was unable to establish whether the laminate had been damaged in this area. Hammer testing of the area was inconclusive, but the permanent deformation of the gel-coat suggested that some damage to the laminate had occured.
For this defect, I recommended that: The damaged gel-coat is cut back to sound laminate. The laminate should then be thoroughly cleaned and dried. Any removed laminate shall be replaced and the repairs finished with epoxy gel-coat. Additional laminate should be applied to the internal surface of the cockpit and bulkhead in these areas in order to stiffen the coaming to bulkhead join and to decrease the likelihood of this problem recurring.
For this defect, I recommended that: The damaged gel-coat is cut back to sound laminate. The laminate should then be thoroughly cleaned and dried. Any removed laminate shall be replaced and the repairs finished with epoxy gel-coat. Additional laminate should be applied to the internal surface of the cockpit and bulkhead in these areas in order to stiffen the coaming to bulkhead join and to decrease the likelihood of this problem recurring.
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